Random phage-epitope library based identification of a peptide antagonist of Mac-1 β2 integrin ligand binding

► A peptide (C-RLKEKH-C) mimicking the human CD11b-I-domain binding site was selected by phage display technology. ► It inhibits the binding of fibrinogen, complement protein iC3b, but not ICAM-1, to CD11b/CD18 integrin. ► The adhesion of PMNs to firbrinogen, and iC3b was blocked by the characterized peptide. ► The anti-inflammatory activity of the peptide was examined in a mouse model.